Hi,
What Jesus means by no-man coming to the father except by me means, that no one will be able to reach God or have a relationship with God unless they come by him. Coming by him means coming by way of the cross, repentance, new birth.
Purgatory is a catholic doctrine and is extra-biblical, it cannot be found in the bible at all.
Children are all covered by the grace of God until they reach an age of understanding, usually around 13, but it can be earlier or later. A child who is brought up in the love of God and who feels the love of God will often of their own mind realise that they have to have a right relationship with God.
Children who die before this time, either through miscarraige or abortions or just before the age of understanding tare all automatically with the Father.
Your point number two, Jesus is a loving person but his is also righteous. He loved us enough to die for us and our sins, however his nature also cannot tolerate sin, so after having provided a way to the father through repentance, and a changed life he expects us to take it. When we look at the nature of God/Jesus we must take in the whole counsel of the word of God, God is Love yes, but God is also wrath.
Another Jesus has been created by people who want to take away the side of Jesus that requires repentance, they have made hime into some kind of new age, soft gooey fuzzy. This is not the true nature of Jesus as shown in the Bible. Jesus loved the little children but he also took a whip to the money-changers in the temple.
It is important that we let the Bible only give the true nature of God and Jesus.
Like you said I am not up for debate with athiests, should you feel you would like to abuse me then go ahead, as the bible tells me I am blessed when you do.